Anatomical proximation of eye with the intracranial space indicates potential relation between cerebrospinal fluid pressure and intraocular pressure.
Based on their similarity and apparent relationship, non-invasive measurement of intraocular pressure might substitute for lumbar puncture for measuring cerebrospinal fluid pressure in near future.
Hospital based prospective cohort study.
120 patients after their informed consent and approval by institutional ethical committee. All patients who were above 18 years; could give consent and who underwent lumber puncture for any neurological symptom or diagnostic reasons and intraocular pressure was measured using Schiotz tonometer, were eligible for this study.
Chi square test between ordinal (intraocular pressure) and categorical (intracranial pressure) values, and linear regression for ordinal (both intraocular pressure and intracranial pressure) values.
68.5% (89/120) of patients had normal intracranial pressure between 5 and 15 mmhg, while 29.2% (38/120) of patients had elevated intracranial pressure of more than 15 mmhg. regarding mean intraocular pressure values, 6.9% (9/120) of patients had lower intraocular pressure, less than 10 mmhg: 90.8% (118/120) of patients with normal intraocular pressure between 10 and 21 mmhg, the other 2.3% (3/120) of patients with higher intraocular pressure more than 21 mmhg. our results showed that intracranial pressure was significantly and positively correlated with intraocular pressure intracranial pressure was correlated significantly with intraocular pressure of the right eyes and intraocular pressure of the left eyes and mean intraocular pressure (MIOP) of both eyes.
The findings in our study are statistically significant suggest that the elevated intracranial pressure may have acted as a counter pressure across the lamina cribrosa to compensate for the elevated intraocular pressure. This correlation is helpful in proving that intraocular pressure can replace invasive modalities for intracranial pressure in the near future.